How do I get one of my cd drive to also be a dvd drive

I have a HL-DT-ST-CD-RW GCE as a drive( LG product), on hardware the type say “dvd/cd rom drives, then I have a LITE ON ltn 48648x max this also say DVD/cd rom drive but neither plays my DVD’s. What do I need to do to be able to view DVDs on my pc. I’m disabled and a student in The America Academy my studies requires me to view and work with some DVD’s( I’m 3 lessons behind in my classes. Please can someone help me? I wish to thank everybody in advance for their help and knowledge. ( my pc was donated to me for my education / retraining in a new field with my dis -ablities) Newschoolgirl44